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Subject: Re: [RFC PATCH 0/2] TPM derived keys
From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Ignat Korchagin <ignat@cloudflare.com>, Jarkko Sakkinen
 <jarkko@kernel.org>
Cc: Mimi Zohar <zohar@linux.ibm.com>, David Howells <dhowells@redhat.com>, 
 Paul Moore <paul@paul-moore.com>, James Morris <jmorris@namei.org>,
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Date: Tue, 14 May 2024 09:30:34 -0600
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On Tue, 2024-05-14 at 14:11 +0100, Ignat Korchagin wrote:
>   * if someone steals one of the disks - we don't want them to see it
> has encrypted data (no LUKS header)

What is the use case that makes this important?  In usual operation
over the network, the fact that we're setting up encryption is easily
identifiable to any packet sniffer (DHE key exchanges are fairly easy
to fingerprint), but security relies on the fact that even knowing that
we're setting up encryption, the attacker can't gain access to it.  The
fact that we are setting up encryption isn't seen as a useful thing to
conceal, so why is it important for your encrypted disk use case?

James